But royal experts herald the arrival of the American actress into boyfriend Prince Harry's life as serendipitous timing, bringing with her a certain je ne sais quoi not seen since his late mother Princess Diana. While sister-in-law Kate Middleton is often criticised by the media for her worst crime of all - being "boring" and quiet - she's widely beloved, with even Prince William acknowledging that the public tend to prefer a visit from his glamorous wife over him.

But Harry has always been a rogue, the daring one who didn't have the same stresses of pomp and decorum as the future King of England. And it appears his girlfriend of 18 months has the same joie de vivre and her self-assurance is rubbing off on her other half for the better.

"She's clearly very self-assured, fearless even. in that respect, she is really a breath of fresh air. She's not a blank canvas on to which royals can project an image, but already has a clear idea of who she is and what she wants to achieve. You haven't seen anyone like this since Diana," royal author Katie Nicholl told Grazia.

"Meghan doesn't seem to be intimidated by the royal family. She has taken everything in her stride and handled her foray into the royal family with impressive confidence.

"Having observed Harry for the past decade, it's very apparent to me that she's had a really positive influence on him. He's dropped his guard and really seems to be enjoying life. We've heard from him more than ever before and he's been honest about his mother, to his great credit. It feels like he's met the right woman at the right time in his life."

While most women have to give up their lives (as they know it) when they marry a prince, Markle is reportedly ready to move on from acting and her career defining role as Rachel Zane in US legal drama Suits.

"Meghan has privately told friends she feels she has reached the pinnacle of her career and has enjoyed her success. What she really wants to do is focus on her humanitarian work - her interest in philanthropy is genuine," a source told the mag. "As Prince Harry's girlfriend and possible fiancée, she will have a unique spotlight on her. She feels she can make a real difference."